Fixed detachable dental attachment device, assembly and methods of using the same

ABSTRACT

A fixed, detachable dental attachment device comprising a cap for securing a dental appliance, a ring, and an abutment to attachment to a tooth root or implant. Also described herein are methods of securing a dental appliance in a subject&#39;s mouth by means of the dental attachment device. Further described herein is a dental attachment device for immediate load on a provisional denture and then incorporated into the final restoration

RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 13/491,002, filed on Jun. 7, 2012, which claims priority toU.S. Provisional Patent Application No. 61/494,544, filed Jun. 8, 2011,and the contents of the aforementioned applications are incorporated byreference herein in their entirety to the extent permitted by law.

FIELD

The present invention relates to fixed detachable dental attachmentdevices and assemblies, and methods of using the same for securing adental appliance.

BACKGROUND

A denture is a prosthetic device constructed to replace some or all ofthe missing natural teeth in a patient's mouth. There are two types ofdentures: a partial denture and a complete denture. The partial denturereplaces a few missing teeth, while the complete denture substitutes theentire maxillary and/or mandibular arch. Dentures can be secured todental implants or non-vital tooth roots in the mouth of a patient usingeither a removable or fixed attachment system. In general, a removabledenture is designed and fabricated to be attached to dental implants andremoved by the patient, whereas a fixed denture is attached to dentalimplants using cement or screws and can only be removed by a dental careprovider.

Both the removable and fixed implant supported dentures have theiradvantages and disadvantages. Common advantages for both the removableand fixed dentures include: proper chewing, protection of the gums, andimprovement in speech and aesthetics. Removable dentures are less costlyand allow for easier cleaning to promote oral hygiene on a daily basisand fewer long-term treatment complications. However, they lack the feelof natural teeth and require more maintenance, e.g., replacement and/oradjustment of attachments and attachment components. In contrast, fixeddentures feel more like natural teeth with less food entrapment and lessmaintenance. Fixed dentures also distribute occlusal loading onto theimplant and onto the jaw bone, which can be beneficial to maintenance ofthe bone ridge height and thickness, bone quality, and oral and facialaesthetics. Nevertheless, fixed dentures are more expensive and moredifficult in terms of long-term treatment complications.

Conventional fixed dental implant attachments systems generally havehigher treatment costs and involve more complicated procedures. The costof components and laboratory fees contribute, in part, to high treatmentcosts that restrict access of such conventional fixed attachmentsystems. At the same time, complicated techniques, such as accommodatingimplant angulations, verification try-ins, and difficulty withadministering cement and/or screws, increase complexity that requireshighly skilled dental care providers, which further adds to the highcost of treatment. Likewise, maintenance of conventional fixedattachment system require time consuming procedure and high cost as thesystem and/or system components must be removed and replaced at recallappointments.

Accordingly, there is a need in the art for a simple, low cost,screwless, cementless, fixed dental implant attachment system that isdetachable by the dental care provider, but at the same time providesthe benefits of a fixed dental attachment system. Disclosed herein is aunique, simple, lower cost, fixed but clinically detachable device forthose patients who want the advantages of a “fixed” implant supporteddenture but cannot afford the current higher end options, and an entrypoint allowing less experienced dentists to perform fixed restorationsdue to an easier restorative procedure. Further described herein is adental implant attachment device that can provide for immediate load(function), through components that can be easily used with theprovisional denture and then incorporated into the final restoration.

SUMMARY OF THE INVENTION

Described herein is a detachable fixed dental attachment device, adental attachment assembly, and methods of securing a dental appliancein a subject's mouth using the same. In one embodiment, a dentalattachment device comprises a cap for securing a dental appliance, aretainer ring, and an abutment. The cap may be integral with a dentalappliance, such as a full denture, overdenture, or partial denture.Depending on the extent of the dental appliance, one or more abutmentsmay be present in the subject's mouth with corresponding caps beingintegral with the dental appliance.

Though the fixed detachable abutment and denture cap have internalfeatures generally consistent with the geometry of O-Ring or O-Ballattachment systems, it is substantially differentiated in two principalways. First, the fixed detachable abutment is designed to rigidlyconnect the prosthesis (i.e. denture) to dental implants and remain inplace with only periodic removal (i.e. once or twice a year for hygienemaintenance) by a clinician with use of a tool specifically designed forthat purpose. Conversely, O-Ring or O-Ball attachment systems providesubstantially less retentive force and are designed to be used with aremovable prosthesis, allowing the patient to easily take out andreplace their denture on a routine (i.e. daily) basis.

Second, the fixed detachable abutment system attaches the prosthesisdirectly to a dental implant thereby transferring all mastication loadsto a series of implants that are integrated in the patient's jaw. TheO-Ring or O-Ball systems are solely intended to provide resilientretention of the denture in the mouth with the prosthesis seatingdirectly on the soft tissue, or gingiva, which absorbs substantially allintra-oral forces such as those from mastication. This is an importantdistinction as tissue borne dentures are typically more uncomfortablefor a patient because the prosthesis can compress, abrade and pinch thegums during chewing function.

Other embodiments, objects, features, and advantages will be set forthin the detailed description of the embodiments that follow and, in part,will be apparent from the description or may be learned by practice ofthe claimed invention. These objects and advantages will be realized andattained by the devices, assemblies, and methods described and claimedherein. The foregoing Summary has been made with the understanding thatit is to be considered as a brief and general synopsis of some of theembodiments disclosed herein, is provided solely for the benefit andconvenience of the reader, and is not intended to limit in any mannerthe scope, or range of equivalents, to which the appended claims arelawfully entitled.

BRIEF DESCRIPTION OF THE DRAWINGS

The details of the present invention, both as to its structure andoperation, may be gleaned in part by study of the accompanying drawings,in which like reference numerals refer to like parts, and in which:

FIG. 1 is an exploded view of the dental attachment device.

FIG. 2 is a perspective view of a cap.

FIG. 3 is a side view of FIG. 2.

FIG. 4 is a cross-sectional view of FIG. 3.

FIG. 5 is a side view of a cap having a short post attachment.

FIG. 6 is a side view of a cap having a screw attachment.

FIG. 7 is a side view of a cap having an adhesive attachment.

FIG. 8 is a side view of an abutment.

FIG. 9 is a cross-sectional view of FIG. 8.

FIG. 10 is a side view of a ring.

FIG. 11 is a cross-sectional view of FIG. 10.

FIG. 12 is a side view of the assembled dental attachment device of FIG.1.

FIG. 13 is a cross-sectional view of FIG. 12.

FIG. 14 is a side view of the assembled dental attachment device of FIG.1 with a divergence between the cap and abutment.

FIG. 15 is a cross-sectional view of FIG. 14.

FIG. 16 is a perspective view of 20° pre-angled abutment.

FIG. 17 is a side view of FIG. 16.

FIG. 18 is a cross-sectional view of FIG. 17.

FIG. 19 is a side view of the assembled dental attachment device with a20° pre-angled abutment of FIG. 16

FIG. 20 is a cross-sectional view of FIG. 19.

FIG. 21 is an alternative embodiment of a 20°pre-angled abutment.

FIG. 22 is a cross-sectional view of FIG. 21.

FIG. 23 is a side view of the assembled dental attachment device with a20° pre-angled abutment of FIG. 21

FIG. 24 is a cross-sectional view of FIG. 23.

FIG. 25 is a perspective view of a healing cap.

FIG. 26 is a side view of FIG. 25.

FIG. 27 is a cross-sectional view of FIG. 26.

FIG. 28 is a side view of assembled healing cap on an abutment.

FIG. 29 is a cross-sectional view of FIG. 28.

FIG. 30 is a perspective view of curved bar.

FIG. 31 is a top view of FIG. 30.

DETAILED DESCRIPTION

While the present invention is capable of being embodied in variousforms, the description below of several embodiments is made with theunderstanding that the present disclosure is to be considered as anexemplification of the claimed subject matter, and is not intended tolimit the appended claims to the specific embodiments illustrated and/ordescribed, and should not be construed to limit the scope or breadth ofthe present invention. The headings used throughout this disclosure areprovided for convenience only and are not to be construed to limit theclaims in any way. Embodiments illustrated under any heading may becombined with embodiments illustrated under any other heading.

In certain embodiments, the present invention relates to a detachabledental attachment device, comprising a cap, a ring, and an abutment. Thecap secures a dental appliance and has an open end and an inner cavitythat forms an annular wall surrounding a retention head. The abutmentcomprises an upper portion having a convex outer surface. The convexouter surface has an open end and an internal socket for receiving thering and engaging the retention head. The dental appliance may besecured in a subject's mouth by attaching the abutment into an existingnon-vital tooth root or implant, aligning the cap over the abutment, andengaging the retention head through the ring and into the socket of theabutment thereby securing the cap (and dental appliance) onto theabutment.

The fixed detachable abutment and denture cap described herein haveinternal features generally consistent with the O-Ring or O-Ballattachment systems, however, it is substantially differentiated in twoprincipal ways. First, the fixed detachable abutment is designed torigidly connect the prosthesis to dental implants and remain in placewith only periodic removal by a clinician with use of a toolspecifically designed for that purpose. Conversely, O-Ring or O-Ballattachment systems provide substantially less retentive force and aredesigned to be used with a removable prosthesis, allowing the patient toeasily take out and replace their denture on a daily basis. Second, thefixed detachable abutment system attaches the prosthesis directly to adental implant thereby transferring all mastication loads to a series ofimplants that are integrated in the patient's jaw. In contrast, theO-Ring or O-Ball systems are solely intended to provide resilientretention of the denture in the mouth with the prosthesis seatingdirectly on the soft tissue, or gingiva, which absorbs substantially allintra-oral forces such as those from mastication. This is an importantdistinction as tissue borne dentures are typically more uncomfortablefor a patient because the prosthesis can compress, abrade and pinch thegums during chewing function.

The present invention further contemplates a kit comprising one or moredetachable dental attachment devices and one or more tools designed forperiodic removal.

FIG. 1 illustrates one embodiment of the dental attachment device forsecuring a dental appliance in the mouth of a subject. FIG. 1 is anexploded view of the dental attachment device 10 comprising: a cap 80for securing in the dental appliance, an abutment 20 for attachment to anon-vital tooth root, implant or the like, and a retainer ring 50. Thecap 80 engages with the abutment 20 and ring 50 as indicated by thecenter line of FIG. 1 to secure a dental appliance in the mouth of asubject. The abutment 20 may be adapted to be compatible withcommercially available implants, such as the Astra implant (Astra TechInc., Waltham, Mass.), Branemark implant (Nobel Biocare, Zurich,Switzerland), and the Straumann implants (Straumann USA LLC, Andover,Mass.), or configured as a tooth root abutment, mini-implant, or in aconfiguration that can be adapted to an intermediary abutment, whichwould be secured to a dental implant. Likewise, the cap 80 may bedesigned to integrate in a dental appliance by means of, for example butnot limited to, a post, a screw, or an adhesive, such as acrylic,bisacrylic, or other dental cements. Dental appliances include, but arenot limited to, full dentures, overdentures, and partial dentures. Thus,depending on the extent of the dental appliance, one or more dentalattachment devices 10 may be used to fix the dental appliance in thepatient's mouth.

FIGS. 2 to 4 illustrate one embodiment of the cap 80. The cap 80comprises a first attachment portion 100 and a body portion 75, the bodyportion 75 having an open end 83 and an inner cavity 95 forming anannular wall 90. The body portion 75 may be any shape suitable forsecuring the cap 80 in a dental appliance. By way of example, FIGS. 2 to4 represent the outer shape as generally cup-shaped or cylindrical. Theinner cavity 95 has an inner annular surface 92 with a distal endportion having a concave lip 97. The concave lip 97 is designed tocorrespond with the outer convex surface 35 of the abutment 20. Theannular wall 90 surrounds a retention head 85 comprising a head portion87 and a shaft 89. The head portion 87 is substantially spherical orball-shaped. In alternative embodiments, the head portion 87 may besubstantially polygonal or spheroid. The head portion 87 can projectabove the lip of the annular wall 90. In an alternative embodiment, thehead portion 87 can be level or below the lip of the annular wall 90.The first attachment portion 100 is provided to secure in the dentalappliance by structures or techniques well known and understood by thoseskilled in the art, including but not limited to, a short post (FIG. 5),a screw (FIG. 6), or an adhesive (FIG. 7). Such methods and techniqueswill not be repeated herein, and the figures are provided as exemplaryonly and not meant to limit the techniques of attaching the cap to adental appliance.

In one embodiment, the cap 80 can be integral with the dental applianceand made of titanium, titanium alloys, cobalt-chromium-molybdenumalloys, stainless steel with a titanium nitride coating, zirconium,tantalum, gold, platinum, palladium, hafnium and tungsten, as well asother materials known to those of skill in the art. Both the firstattachment portion 100 and body portion 75 may be recessed in the dentalappliance. In another embodiment, the body portion 75 may be partiallyrecessed in the dental appliance. In still another embodiment, only thefirst attachment portion 100 may be recessed in the dental appliance.

In one embodiment of the cap 20, the head portion 87 has a diameter inthe range of about 0.05 in to about 0.15 in. Illustratively, thediameter of the head portion 87 is about 0.05 in, about 0.06 in, about0.07 in, about 0.08 in, about 0.09 in, about 0.10 in, about 0.11 in,about 0.12 in, about 0.13 in, about 0.14 in, and about 0.15 in.

FIGS. 8 and 9 illustrate one embodiment of the abutment 20. The abutmentcomprises a upper portion 30 having an open end 32 and a socket 34 forreceiving the ring 50 and the retention head 85 of the cap 80, a cuffportion 37, and a second attachment portion 25 for attachment to anon-vital tooth root or implant. The upper portion 30 has a convex outersurface 35 extending from the open end 32 to the cuff portion 37. Thecuff portion 37 may be of different heights to accommodate patients withdifferent tissue heights. The socket 34 extends from the open end 32through part or all of the length of the upper portion 30 and/or cuffportion 37, and is designed to accommodate the ring 50 and the retentionhead 85 of the cap. The socket 34 has an annular lip 41, an annular ring42, a cylindrical cavity 44, and a hemispherical or bowl-shaped portion46. The cavity 44 receives the ring 50 by snap-engagement over theannular ring 42 of the abutment 20, which fits into the correspondingannular groove 60 of the ring 50. The head portion 87 of the retentionhead 85 snap-fits through the ring 50 and is positioned in thehemispherical portion 46, securing the cap onto the abutment. Atool-receiving bore 48 extends inwardly from the bottom of the socket 34and can be threaded or polygonal, for example, hexagonal with flatfaces, for engagement by a suitable tool for attaching the abutment 20to a non-vital tooth root or implant. The second attachment portion 25can be adapted to be compatible with commercially available implants, orconfigured as a tooth root abutment, mini-implant, or an intermediaryabutment as discussed below.

The abutment 20 described herein can be made of suitably strong materialsuch as titanium, titanium alloys, cobalt-chromium-molybdenum alloys,stainless steel with a titanium nitride coating, zirconium, tantalum,gold, platinum, palladium, hafnium and tungsten, as well as othermaterials known to those of skill in the art. The abutment 20 can bemade in a range of different sizes to fit a number of differentimplants, tooth roots, or intermediary abutment. The length of theabutment 20 is in the range of about 1 mm to about 10 mm. In furtherembodiments, the length can be about 1 mm, about 2 mm, about 3 mm, about4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, andabout 10 mm.

The ring 50, shown in FIGS. 10 and 11, is adapted for engagement in thesocket 34 of the abutment 20 for retention of cap 80, which is integralwith the dental appliance. Referring to FIG. 10, the ring 50 has twoannular flanges 55 and 57 separated by an annular seat or groove 60 toreceive the corresponding annular ring 42 in the socket 34 of theabutment 80. The inner surface 65 of the ring 50, as shown in FIG. 11,is inwardly tapered from both the top and bottom, forming an hour-glassshape. The ring 50 can be made of suitably durable and flexible materialsuch as nylon, PEEK, delrin, and other polymers known in the art, andmetals such as titanium, stainless steel, etc., as well as othermaterials known to those of skill in the art.

FIGS. 12 and 13 illustrate one embodiment of the assembled dentalattachment device for securing a dental appliance in the mouth of apatient. To assemble the dental attachment device, the ring 50 is snapfit over the annular ring 42 into the cylindrical cavity 44. The cap 80(which can be integral with a dental appliance) is positioned over theabutment, and the retention head 85 is engaged into the socket 34 andsnap fit through the ring 50. The head portion 87, or a portion thereof,is received into the hemispherical or bowl-shaped portion 46. Thesnap-fit engagement of the head portion 87 of the retention head 85 andring 50 secures the cap onto the abutment. At the same time, the annularwall 90, in particular the concave lip 97, is engaged over the convexouter surface 35 of the abutment 20. The frictional forces, as well asthe angle of convergence, between the two corresponding surfaces 97 and35 also secures the cap to the abutment, while at the same time allowfor a range of divergence between the cap 80 relative to the abutment20. The tightened fit between the cap 80 and abutment 20 helps to sealthe device from oral fluids in an effort to prevent microbialcontamination and plaque traps.

Referring to FIGS. 14 and 15, when the dental attachment device 10 isassembled, there is a gap 110 between the cap 80 and the abutment 20 anda gap 120 between the ball-type head portion 87 and the hemispherical orbowl-shaped portion 44, which allows the cap 20 to diverge or pivot orswivel relative to the abutment 20. The range of divergence between thecap 80 and abutment 20 is 0° to about 20°. Illustratively, the capdiverges relative to the abutment at an angle of 0°, about 1°, about 2°,about 3°, about 4°, about 5°, about 6°, about 7°, about 8°, about 9°,about 10°, about 11°, about 12°, about 13°, about 14°, about 15°, about16°, about 17°, about 18°, about 19°, and about 20°. The divergence ofthe cap 80 relative to the abutment 20 is shown as reference numerical115. However, even at the range of divergence, the annular wall 90 (andconcave lip 97) maintains contact with the outer surface 35 of theabutment 20 to ensure frictional contact and help to create a sealbetween the cap 80 and abutment 20.

FIGS. 16 to 18 illustrate one embodiment of a pre-angled abutment 200.The pre-angled abutment 200 is similar to that of the previousembodiment described in FIGS. 8 to 9. Referring to FIGS. 16 to 18, thepre-angled abutment 200 comprises an upper portion 230, a cuff portion237, a second attachment portion 225, and a through bore 239. Thethrough bore 239 comprises a first portion 240 and a second portion 250.The first portion 240 is similar to socket 34 of FIG. 9, having anannular lip 241, annular ring 242, a cylindrical cavity 244, and a lowerportion 246. The cavity 244 receives the ring 50 by snap-engagement overthe annular ring 42 of abutment 20, which fits into the correspondingannular groove 60 of the ring 50. The head portion 87 of the retentionhead 85 snap-fits through the ring 50 and is positioned in the lowerportion 246. The second portion 250 comprises a first cylindricalportion 252, that accepts a retaining screw to fasten a pre-angledabutment to an implant, and a second cylindrical portion 254, the secondcylindrical portion 254 having a smaller diameter than the firstcylindrical portion 252.

In one embodiment, the upper portion 230 is at an angled of 20°. from acentral axis of the cuff 237 and attachment 225 portions as shown inFIG. 18. The pre-angled abutment is exemplary and not limiting as thepre-angled abutment can be at an angle of, about 10° about 15, about20°, and about 25°. In additional embodiments, the pre-angle abutmentcan be at an angle between about 5° to about 45°, about 10° to about40°, about 15° to about 35°, and about 20° to about 30°. By way ofexample, the 20° pre-angled abutment, together with the range ofdivergence, allows a divergence up to about 40° of the cap 80 relativeto the central axis of the cuff 237 and attachment 225 portions of theabutment 20. Illustratively, the range of divergence of the cap 20 isabout 20°, about 21°, about 22°, about 23°, about 24°, about 25°, about26°, about 27°, about 28°, about 29°, about 30°, about 31°, about 32°,about 33°, about 34°, about 35°, about 36°, about 37°, about 38°, about39°, and about 400° relative to the 20° pre-angled abutment 200.

Referring to FIGS. 19 and 20, the pre-angled abutment 200 can be securedin an implant 233 by means of the second attachment portion 225, whichis secured in an implant using a retaining screw 260. The implant 233comprises a first end cuff portion 232 having an open end comprising acavity 238 for receiving the second attachment portion 225 of thepre-angled abutment 200 and a threaded bore 236, and a second end threadshaft 243. The cavity 238 is designed in size and shape to mate with thesecond attachment portion 225 of abutment 200. For assembly, the secondattachment portion 225 of the pre-angled abutment 200 is fitted into thecavity 238 of the implant 233. The retaining screw 260 is set throughthe through bore 239 and screwed into the threaded bore 236, therebysecuring the pre-angled abutment 200 to the implant 230.

An alternative embodiment of a two-piece pre-angled abutment 200′ isillustrated in FIGS. 21 and 22. The pre-angled abutment 200′ is similarto that of the previous embodiment described in FIGS. 16 to 18, and likereference numbers will be used for like parts. The pre-angled abutment200′ comprises a first component 215 having an upper portion 230 and athreaded shaft 227, and a second component 220 having a body portion231, a second attachment portion 225, and through bore 239. The upperportion 230 has an open end 232 and a socket 234 for receiving the ring50 and the retention head 85 of the cap 80, and a convex outer surface235 extending from an open end 232 to the threaded shaft 227. The socket234 has an annular lip 241, annular ring 242, a cylindrical cavity 244,and a lower portion 246. A tool-receiving bore 245 extends inwardly fromthe bottom of the socket 234. The body portion 231 has a open end 247and a cavity having a thread portion 251, a first cylindrical portion252, and a second cylindrical portion 254 having a smaller diameter thanthe first cylindrical portion 252.

The thread portion 251 is at a predetermined angled 115 from a centralaxis of the first and second cylindrical portions 252 and 254,respectively, and in turn, when assembled, the first component will beat the same predetermine angle. For example, the pre-angled abutment canbe at an angle of, about 10°, about 15, about 20°, and about 25°. Inadditional embodiments, the pre-angle abutment can be at an anglebetween about 5° to about 45°, about 10° to about 40°, about 15° toabout 35°, and about 20° to about 30°. By way of example, the 20°pre-angled abutment, together with the range of divergence, allows adivergence up to about 40° of the cap 80 relative to the first andsecond cylindrical portions 252 and 254, respectively, of the abutment200′. Illustratively, the range of divergence of the cap 20 is about20°, about 21°, about 22°, about 23°, about 24°, about 25°, about 26°,about 27°, about 28°, about 29°, about 30°, about 31°, about 32°, about33°, about 34°, about 35°, about 36°, about 37°, about 38°, about 39°,and about 40° relative to the 20° pre-angled abutment 200′.

The two-piece pre-angled abutment 200′, as shown in FIGS. 23 and 24, canbe assembled and secured in an implant 233 using a retaining screw 260as shown in FIG. 24. The second attachment portion 225 of the secondcomponent 220 is fitted into cavity 238 of the implant 233. Theretaining screw 260 is set through the through bore 239 and screwed intothe threaded bore 236, thereby securing the second component 220 to theimplant 230. The threaded shaft 227 of the first component 215 isengaged and secured into the threaded portion 251 of the cavity 236 ofthe second component 220.

Another embodiment of the abutment is incorporated as a mini implant forosseo-integration into the jawbone of a subject. A mini implant is asmall-diameter, one-piece root form implant that osseo-integrates intothe jawbone and allows immediate loading of a dental appliance. The miniimplant come in a number of different sizes. The shaft may range indiameter from about 1.8 mm to about 2.9 mm. Illustratively, the diameterof the shaft may be about 1.8 mm, about 1.9 mm, about 2.0 mm, about 2.1mm, about 2.2 mm, about 2.3 mm, about 2.4 mm, about 2.5 mm, about 2.6mm, about 2.7 mm, about 2.8 mm and about 2.9 mm. Further, the length ofthe shaft ranges from about 10 mm to about 18 mm. In furtherembodiments, the length may be about 10 mm, about 11 mm, about 12 mm,about 13 mm, about 14 mm, about 15 mm, about 16 mm, about 17 mm, andabout 18 mm.

FIGS. 25 to 27 illustrate one embodiment of a healing cap 300. Thehealing cap 300 comprises an upper surface 310 that is generally flatand an annular skirt 320 projecting downwardly from the upper surface310 to surround a shaft 330. The shaft comprises a distal threadedportion 333 and a coaxial trunco-conical section 340. A tool-receivingbore 345 extends inwardly from the upper surface 310. The tool-receivingbore 345 can be, for example hexagonal with flat faces, for engagementby a suitable tool.

Referring to FIGS. 28 and 29, the healing cap 300 is positioned over thesocket 34 of the abutment 20 and the shaft is engaged through the ring50 and screwed into the threaded bore 48. The tapered inner surface 65of the ring 50 matches the trunco-conical section 340 of the shaft 330of the healing cap 300. At the same time, the annular skirt 320 isengaged and tightened over the outer surface 35 of the abutment 80. Thefit between the healing cap 300 and abutment 20 can help to create aseal that minimizes the penetration of oral fluids into the abutmentcavity in an effort to prevent microbial contamination.

FIGS. 30 and 31 illustrates one embodiment of a curved bar attachment400. The bar attachment 400 can be used to connect two or more dentalattachment devices 10 to a rigid frame for a full denture, overdentureor partial denture. The bar 400 can be made in a number of differentsizes to accommodate varying patients' dental arch, for example, small,medium, large, and extra large, and made of suitably strong materialsuch as titanium, titanium alloys, cobalt-chromium-molybdenum alloys,stainless steel with a titanium nitride coating, zirconium, tantalum,gold, platinum, palladium, hafnium and tungsten, as well as othermaterials known to those of skill in the art. The bar may also be cutinto partial arch shapes that are both straight and curved of variouslengths.

The above description of the disclosed embodiments is provided to enableany person skilled in the art to make or use the invention. Variousmodifications to these embodiments will be readily apparent to thoseskilled in the art, and the generic principles described herein can beapplied to other embodiments without departing from the spirit or scopeof the invention. Thus, it is to be understood that the description anddrawings presented herein are representative of the subject matter whichis broadly contemplated by the present invention. It is furtherunderstood that the scope of the present invention is not intended to belimited to the embodiment shown herein but is to be accorded the widestscope consistent with the patent law and the principles and novelfeatures disclosed herein.

All references, including publications, patent applications, andpatents, cited herein are hereby incorporated by reference to the sameextent as if each reference were individually and specifically indicatedto be incorporated by reference and were set forth in its entiretyherein.

The use of the terms “a,” “an” and “the” and similar references in thecontext of this disclosure (especially in the context of the followingclaims) are to be construed to cover both the singular and the plural,unless otherwise indicated herein or clearly contradicted by context.All methods described herein can be performed in any suitable orderunless otherwise indicated herein or otherwise clearly contradicted bycontext. The use of any and all examples, or exemplary language (e.g.,such as, preferred, preferably) provided herein, is intended merely tofurther illustrate the content of the disclosure and does not pose alimitation on the scope of the claims. No language in the specificationshould be construed as indicating any non-claimed element as essentialto the practice of the present disclosure.

Alternative embodiments of the claimed disclosure are described herein,including the best mode known to the inventors for practicing theclaimed invention. Of these, variations of the disclosed embodimentswill become apparent to those of ordinary skill in the art upon readingthe foregoing disclosure. The inventors expect skilled artisans toemploy such variations as appropriate (e.g., altering or combiningfeatures or embodiments), and the inventors intend for the invention tobe practiced otherwise than as specifically described herein.

Accordingly, this invention includes all modifications and equivalentsof the subject matter recited in the claims appended hereto as permittedby applicable law. Moreover, any combination of the above describedelements in all possible variations thereof is encompassed by theinvention unless otherwise indicated herein or otherwise clearlycontradicted by context.

The use of individual numerical values are stated as approximations asthough the values were preceded by the word “about” or “approximately.”Similarly, the numerical values in the various ranges specified in thisapplication, unless expressly indicated otherwise, are stated asapproximations as though the minimum and maximum values within thestated ranges were both preceded by the word “about” or “approximately.”In this manner, variations above and below the stated ranges can be usedto achieve substantially the same results as values within the ranges.As used herein, the terms “about” and “approximately” when referring toa numerical value shall have their plain and ordinary meanings to aperson of ordinary skill in the art to which the disclosed subjectmatter is most closely related or the art relevant to the range orelement at issue. The amount of broadening from the strict numericalboundary depends upon many factors. For example, some of the factorswhich may be considered include the criticality of the element and/orthe effect a given amount of variation will have on the performance ofthe claimed subject matter, as well as other considerations known tothose of skill in the art. As used herein, the use of differing amountsof significant digits for different numerical values is not meant tolimit how the use of the words “about” or “approximately” will serve tobroaden a particular numerical value or range. Thus, as a generalmatter, “about” or “approximately” broaden the numerical value. Also,the disclosure of ranges is intended as a continuous range includingevery value between the minimum and maximum values plus the broadeningof the range afforded by the use of the term “about” or “approximately.”Thus, recitation of ranges of values herein are merely intended to serveas a shorthand method of referring individually to each separate valuefalling within the range, unless otherwise indicated herein, and eachseparate value is incorporated into the specification as if it wereindividually recited herein.

1. A fixed detachable dental attachment device, comprising: a cap forsecuring a dental appliance having an open end and an inner cavityforming an annular wall that surrounds a retention head, the annularwall having a concave portion extending up to the open end, and a firstattachment portion; an abutment comprising an upper portion and a secondattachment portion, the second attachment portion having a central axis,wherein the upper portion has a convex outer surface comprising an openend and a socket; an annular ring in the socket, wherein the retentionhead extends into the socket and through the ring to secure the cap ontothe abutment with the convex outer surface of the abutment engaging theconcave portion of the annular wall of the cap; wherein the retentionhead is in swivel engagement in the socket and the concave portion ofthe cap is in swivel engagement with the convex outer surface of theabutment; and the abutment is pre-angled with the upper portion at apredetermined angle in the range from 5 ° to 45° relative to the centralaxis of the second attachment portion.
 2. The device of claim 1, whereinthe retention head comprises a head portion and a shaft.
 3. The deviceof claim 2, wherein the head portion is ball-shaped.
 4. The device ofclaim 2, wherein the head portion is in a shape selected from the groupconsisting of: spherical, polyhedron, and spheroid.
 5. The device ofclaim 1, wherein the abutment further comprises a cuff portion betweenthe upper portion and attachment portion and the cuff portion is alignedwith the central axis of the attachment portion.
 6. The device of claim1, wherein the upper portion of the abutment is pre-angled at about 20°relative to the central axis of the second attachment portion.
 7. Thedevice of claim 1, wherein the upper portion of the abutment ispre-angled at an angle relative to the central axis of the secondattachment portion selected from the group consisting of about 10degrees, about 15°, about 20°, and about 25°.
 8. The device of claim 1,wherein the cap is adapted for swivel engagement on the abutment over apredetermined range of divergence.
 9. The device of claim 8, wherein theinner cavity of the body portion of the cap has an inner end facing theopen end, the abutment has an upper end facing away from the socketwhich is axially spaced from the inner end of the cavity to provide afirst gap between the upper end of the abutment and the opposing innerend of the inner cavity in the cap, and the retention head has an endface spaced from the socket to provide a second gap between theretention head and socket, wherein the first and second gaps permitswivel engagement of the cap on the abutment over the predeterminedrange of divergence.
 10. The device of claim 8, wherein the range ofdivergence between the cap relative to the upper portion of the abutmentis at an angle from 0° to about 20°.
 11. The device of claim 8, whereinthe cap is adapted to diverge relative to the central axis of theattachment portion of the pre-angled abutment at a total angle selectedfrom the group consisting of: about 20°, about 21°, about 22°, about23°, about 24°, about 25°, about 26°, about 27°, about 28°, about 29°,about 30°, about 31°, about 32°, about 33°, about 34°, about 35°, about36°, about 37°, about 38°, about 39°, and about 40°.